From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Mathematical analysis detailing the effect of leakage in hydraulic tappets.
| Identifier | ExFiles\Box 17\6\ Scan289 | |
| Date | 24th July 1934 | |
| To E.{Mr Elliott - Chief Engineer} to By.{R.W. Bailey - Chief Engineer} X7060 Hs{Lord Ernest Hives - Chair}/Smth.3/KW.24.7.34. Effect of Leakage in Hydraulic Tappets. Let L = load on rocker end. k = mechanical advantage of system (i.e. movement of 1 unit of plunger causes movement of k units at rocker end). d = diameter of plunger. b = length of plunger. c = clearance between plunger and casing. --- Then oil pressure under the plunger = total pressure / area ∝ kL / d² For oil of given viscosity, rate of leakage may be taken as proportional to ((clearance)² x oil pressure x circumference of plunger) / (length of plunger) i.e. ∝ (c² kL x d) / (d² x b) ∝ c² KL / db{Donald Bastow - Suspensions} Travel of plunger due to this leakage ∝ Total leakage / area ∝ c²kL / d³b Travel at rocker end ∝ travel of plunger x k ∝ c²k²L / d³b | ||